Chloroplasts can be found in eukaroyotes such as algae and plant cells and they house the process of photosynthesis. They absorb light and use with water and carbon dioxide to make sugars, raw material for energy and biomass to keep free energy in the form of ATP. Choloroplasts also, through photosynthesis, make NADP to NADPH.
Structure
The choloroplast is made up of an outer membrane and an inner membrane. Within these membranes is the stroma. In the stroma are the thakloids which come in stacks called grana (or the singular produced in the above picture: granum). These grana stacks are the site of photosynthesis. Inside the grana stacks is lumen which is a system of vesicles. In the thakloid membranes occurs four different things or the "atenna complex": Photosynthesis I and II, Cytochromes b and f, and ATP sythase which all are involved in the process of the light reactions of photosythesis.
Recent Studies
Department of Plant Physiology, Eötvös Loránd University, Budapest, Hungary, Agricultural Research Institute of the
Hungarian Academy of Sciences, Martonvásár, Hungary.
Researchers: Szabolcs Rudnóy, Zoltán Bratek, Emil Páldi, Ilona Rácz, Demeter Lásztity
Overview: In wheat bread, there are three different genomes. The origins of these three genomes are still a little unclear. In Hexaploid wheat, there is the structure of the three genomes as AABBDD which they believe may have come about through the hybridization of the AABB tetraploid wheat and the D genome diploid. By looking at rDNA and the study sequences of chloroplasts, it has given more knowledge on the evolution of wheat. So, if the B genome can be cleared up about where it came from, even more could be deduced about the evolution of wheat.
Other Plastids
Image:Plastids types.svg
Plastids come from proplastids which can either differentiate depending on function or stay undifferentiated like the examples in the above picture. Platids make several copies of the plastid genome ranging from 100 or less to 1000 and contains about 100 genes.
Also, there is plastid DNA which are large protein DNA complexes and are called plastid nucleoids.
Long, thin protuberances called stromules which come from the body of the plastid to the cytosol and connect together plastids.
Endosymbiosis
The process of endosymbiosis creates endosymbionts. These endosymbionts are organisms that can live in the body or cells of other organisms and it is believed that chloroplasts originated from cyanobacteria.
Chloroplast are the photosynthesizing organelles found in Eukaroyotes such as plant cells and algae. Through photosynthesis, they absorb sunlight and use it to power the synthesis of organic food molecules by converting light energy to chemical energy. A typical cell contains about 10 to 100 chloroplast.
Structure and Function
Chloroplast is partitioned by internal membranes into three major compartments:
1st compartment- located between the outer and inner phospholipids membranes of the chloroplast is the narrow intermembrane space. The intermembrane partitions the contents of the chloroplast from the cytolsol (liquid found inside cells).
2nd compartment- the space enclosed by the inner membrane contains a thick fluid called stroma. In this compartment the stroma contains the chloroplast's circular DNA, special ribosomes, as well as dissolved enzymes and RNA. Those steps that use chemical energy to convert carbon dioxide into sugar occur in the stroma. The stroma contains much of the chloroplast's volume.
3rd compartment- is called the thylakoid space which is inside the tubules and disks. These disks are called thylakoids. Chlorophyll is found in the thylakoid membranes. Thylakoids function in the initial steps of photosynthsis which converts light energy to chemical energy. These disks (thylakoids) are arranged in stacks, each called granum (plural grana). These grana are the chloroplast's solar energy. It is the sight where chlorophyll actually trap the solar energy. Inside the thylakoids is empty space called the lumen.
Plastids
Chloroplast are one of several types of plastids. Plastids are organelles found in plants and algae containing pigments used in photsynethsis. The types of pigments present can determine or change the cell's color. Plastids are involved in the energy storage and synthesis of metabolic materials. All plastids develope from tiny organelles found in immature cells of plant mertistems (undifferentiated plant tissue) called proplastids.
Different types of plastids include:
chloroplast- contains green pigments Chlorophyll A and Chlorophyll B which absorbs the light energy needed for photosynthesis to occur.
leucroplast- contains colorless pigments involved in the synthesis of starches, oils, and proteins
chromopast- contains yellow-to-red pigments which make carotenoids.
Endosymbiosis
Chloroplast is different from most other organelles because it has its own DNA and reproduces independently of the cell in which it is found. Because of these prokaryotic traits, it is said that chloroplast is an endosymbiont (an organism that lives within the body or cells of another organism). The endosymbiosis theory prostulates that the chloroplast of eukaryotes evolved from endosymbiotic cyanbacteria.
Recent Studies
Title: Plastid Tubules of Higher Plants are Tissue-Specific and Developmentally Regulated
Authors: RH Kohler and MR Hanson, Department of Molecular Biology and Genetics, Biotechnology Building Building, Cornell University
Overview: Green fluorescent stroma filled tubules (stromules) were observed coming out from the placid surface in tabbaco plants containing localized green fluorescent protein (GFP). These plants were then examined by epifluorescence and confocal laser scanning microscopy (CSML) to see if there were any developemental and/or cell type specific differences in the number and apperance of stromules and plastids. The reason they did this was because stromules are rarely seen on chlorophyll-containing plastids. However, they are abundant in tissues that contain chlorophyll-free plastids. The morphology of plastids in chlorophyll-free plastids can range. They are often elongated and irregular. The size, shape, and position can also vary in developmental zones in the root. Nevertheless, the cell on the tabacco plant showed stromules on almost every plastid with two major forms of appearance. Through photobleaching expiriments,they were able to indictate that GFP can flow through stromules.
Works Cited
Campbell, Neil A. Biology. 8th ed. San Francisco: Pearson Education, Inc., 2008.
Kohler, R. H., and M. R. Hanson. "Plastid tubules of higher plants are tissue-specific and developmentally regulated." Journal of Cell Science 113.1: 81-89. 14 Oct. 2008 <http://jcs.biologists.org/cgi/content/ abstract/113/1/81>.
Chloroplasts
Chloroplasts can be found in eukaroyotes such as algae and plant cells and they house the process of photosynthesis. They absorb light and use with water and carbon dioxide to make sugars, raw material for energy and biomass to keep free energy in the form of ATP. Choloroplasts also, through photosynthesis, make NADP to NADPH.
Structure
The choloroplast is made up of an outer membrane and an inner membrane. Within these membranes is the stroma. In the stroma are the thakloids which come in stacks called grana (or the singular produced in the above picture: granum). These grana stacks are the site of photosynthesis. Inside the grana stacks is lumen which is a system of vesicles. In the thakloid membranes occurs four different things or the "atenna complex": Photosynthesis I and II, Cytochromes b and f, and ATP sythase which all are involved in the process of the light reactions of photosythesis.Recent Studies
Department of Plant Physiology, Eötvös Loránd University, Budapest, Hungary, Agricultural Research Institute of theHungarian Academy of Sciences, Martonvásár, Hungary.
Researchers: Szabolcs Rudnóy, Zoltán Bratek, Emil Páldi, Ilona Rácz, Demeter Lásztity
Overview: In wheat bread, there are three different genomes. The origins of these three genomes are still a little unclear. In Hexaploid wheat, there is the structure of the three genomes as AABBDD which they believe may have come about through the hybridization of the AABB tetraploid wheat and the D genome diploid. By looking at rDNA and the study sequences of chloroplasts, it has given more knowledge on the evolution of wheat. So, if the B genome can be cleared up about where it came from, even more could be deduced about the evolution of wheat.
Other Plastids
Plastids come from proplastids which can either differentiate depending on function or stay undifferentiated like the examples in the above picture. Platids make several copies of the plastid genome ranging from 100 or less to 1000 and contains about 100 genes.
Also, there is plastid DNA which are large protein DNA complexes and are called plastid nucleoids.
Long, thin protuberances called stromules which come from the body of the plastid to the cytosol and connect together plastids.
Endosymbiosis
The process of endosymbiosis creates endosymbionts. These endosymbionts are organisms that can live in the body or cells of other organisms and it is believed that chloroplasts originated from cyanobacteria.Tyler Frankel
Bibliography
"Chloroplasts." Wikipedia. 08 August 2008. 26 Oct 2008 <http://en.wikipedia.org/wiki/Chloroplast>.
Kimball, John. "Chloroplasts." Kimball's Biology Pages. 10 August 2003. 26 Oct 2008
<http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/C/Chloroplasts.html>.
Perkins, Rodger. "Endosymbiosis - the Origin of Domain Eukarya ." The Virtual. 2002-2008. The Virtual Fossil
Museum. 26 Oct 2008 <http://www.fossilmuseum.net/Evolution/Endosymbiosis.htm>.
"Plastids." Wikipedia. 18 October 2008. 26 Oct 2008 <http://en.wikipedia.org/wiki/Plastid>.
"Studies on chloroplast and nuclear rDNA in hexaploid." 2005. Volume 49(1-2):35-36. 26 Oct 2008
<http://www.sci.u-szeged.hu/ABS/2005/Acta%20HP/4935.pdf>.
Chyna Pinto- Per. G
Chloroplast
Chloroplast are the photosynthesizing organelles found in Eukaroyotes such as plant cells and algae. Through photosynthesis, they absorb sunlight and use it to power the synthesis of organic food molecules by converting light energy to chemical energy. A typical cell contains about 10 to 100 chloroplast.
Structure and Function
Chloroplast is partitioned by internal membranes into three major compartments:Plastids
Chloroplast are one of several types of plastids. Plastids are organelles found in plants and algae containing pigments used in photsynethsis. The types of pigments present can determine or change the cell's color. Plastids are involved in the energy storage and synthesis of metabolic materials. All plastids develope from tiny organelles found in immature cells of plant mertistems (undifferentiated plant tissue) called proplastids.
Different types of plastids include:
Endosymbiosis
Chloroplast is different from most other organelles because it has its own DNA and reproduces independently of the cell in which it is found. Because of these prokaryotic traits, it is said that chloroplast is an endosymbiont (an organism that lives within the body or cells of another organism). The endosymbiosis theory prostulates that the chloroplast of eukaryotes evolved from endosymbiotic cyanbacteria.Recent Studies
Title: Plastid Tubules of Higher Plants are Tissue-Specific and Developmentally RegulatedAuthors: RH Kohler and MR Hanson, Department of Molecular Biology and Genetics, Biotechnology Building Building, Cornell University
Overview: Green fluorescent stroma filled tubules (stromules) were observed coming out from the placid surface in tabbaco plants containing localized green fluorescent protein (GFP). These plants were then examined by epifluorescence and confocal laser scanning microscopy (CSML) to see if there were any developemental and/or cell type specific differences in the number and apperance of stromules and plastids. The reason they did this was because stromules are rarely seen on chlorophyll-containing plastids. However, they are abundant in tissues that contain chlorophyll-free plastids. The morphology of plastids in chlorophyll-free plastids can range. They are often elongated and irregular. The size, shape, and position can also vary in developmental zones in the root. Nevertheless, the cell on the tabacco plant showed stromules on almost every plastid with two major forms of appearance. Through photobleaching expiriments,they were able to indictate that GFP can flow through stromules.
Works Cited
Campbell, Neil A. Biology. 8th ed. San Francisco: Pearson Education, Inc., 2008.
Chloroplast. photograph. National Research Council Canada. 12 Sept. 2005. 19 Oct. 2008 http://www.nrc-cnrc.gc.ca/.../gallery/chloroplast.html.
"Chloroplast." Wikipedia The Free Encyclopedia. 15 Oct. 2008. 12 Oct. 2008 http://en.wikipedia.org/wiki/Chloroplast.
Davidson, Michael W. "Chloroplast." Molecular Expressions Cell Biology and Microscopy Structure and Funtion of Cells & Viruses. 10 Dec. 2004. Florida State University. 22 Oct. 2008 <http:// micro.magnet.fsu.edu/.../ chloroplasts.html>.
"Endosymbiotic Theory." Wikipedia The Free Dictionary. 22 Oct. 2008. 25 Oct. 2008 http://en.wikipedia.org/wiki/Endosymbiotic_theory.
Kohler, R. H., and M. R. Hanson. "Plastid tubules of higher plants are tissue-specific and developmentally regulated." Journal of Cell Science 113.1: 81-89. 14 Oct. 2008 <http://jcs.biologists.org/cgi/content/ abstract/113/1/81>.
Mallory, C. "Photosynthesis." University of Miami. 23 Oct. 2008. 21 Oct. 2008 http://porpax.bio.miami.edu/~cmallery/150/phts/phts.htm.
"Plastid." Wikipedia The Free Encyclopedia. 18 Oct. 2008. 17 Oct. 2008 http://en.wikipedia.org/wiki/Plastid.